Visionaire: A Prospective Study

An interim analysis found the study would not be able to reach significance without a large increase in subjects which was not feasible.

The purpose of the current study is to validate the technology of MRI-based alignment for total knee replacements and to collect data on potential advantages of the computer aided system. It is hypothesized that there will be no significant differences in position, loosening, or function of the Visionaire total knee as compared to the conventional total knee. It is hypothesized that the Visionaire total knee will be significantly better with regard to operative time, tourniquet time, blood loss, and procedural set-up, turnover time, and overall costs.

The Visionaire system is a computer-aided system utilizing MRI of the knee prior to TKA surgeries. This technology achieves accurate rotational and A-P position. All of the commonly-referred anatomical landmarks (AP axis, epicondylar axis) are analyzed pre-operatively, allowing for the proper positioning of the implant for each patient.

A conventional TKA utilizes a jig system based on either intra-medullary or extra-medullary guides. No knee MRI is utilized for a conventional TKA.

Inclusion Criteria: Adult patients with sufficient symptoms from articular knee pathology to be an appropriate candidate for TKA Exclusion Criteria: prior TKA ipsilateral upper tibial or distal femoral osteotomy ipsilateral total hip arthroplasty patient with significant >15o varus or valgus morbid obesity or those patients unable to have an MRI based on thigh circumference (22 cm or less)